Recorder apparatus



Aug. 22, 1939. o. s. PETERS 2,170,505

RECORDER APPARATUS Filed March 26, 1935 2 Sheets-sheet 1 3/ 27 w 29 f 32V 25 m a n g 4 O. S. PETERS Aug. 22,1939. 0. s. PETERS RECORDERAPPARATUS 2 Sheets-Sheet 2 Filed March 26, 1935 II llllllll INVENTOR 05.ezers A ORNE Patented Aug. 22, 1939 2,170,505

UNITED STATES PATENT OFFICE RECORDER APPARATUS Orville S. Peters, ChevyChase, MLL, assignor to Baldwin-Southwark Corporation, a corporation ofDelaware Application March 26, 1935, Serial No. 13,127

2 Claims. (01. 23477) This invention relates generally to materials ingmechanism therefor partly broken away to testing equipment and moreparticularly to apshow details of construction;

paratus for recording the stress-strain relation Fig. 3 is an enlargedtransverse section of the of material stressed in a materials testingmameans for driving and adjusting the stylus taken chine. substantiallyon the line 33 of Fig. 1; 5

Various forms of such stress-strain appara- Fig. 4 is a diagrammaticplan view of the drivtus, generally known as autographic recording ingconnections; devices, have been heretofore proposed and built, Fig. 5 isa longitudinal section of the recorder but the same have involvedcomplications or andrum;

noyances that have deterred or limited their Fig. 6 is a verticalsection taken on line 6-43 10 use, due usually to an undue length oftime to of Fig. 5. prepare the record equipment for use and to sub- Inthe particular embodiment of the invenstitute fresh record sheets,especially when a tion which is shown herein merely for the purlargenumber of successive tests are being made. D SE of llu t at ng O e Spfic form among D It is one object of my invention to provide an sibleothers that the invention might take in 15 improved combination for anautographic repractice, I have provided a stress-strain recordingapparatus whereby fresh record sheets corder having a base I. This basemay contain may be conveniently and expeditiously placed in any suitableautomatic control equipment operuse while at the same time effectivelyobtaining ated in response to stress and strain of a specithe propercooperative relation between the men, one suitable form of suchmechanism being 20 record sheet and the automatic mechanism for shown inpatents of O. S. Peters and G. S. von operating the apparatus inaccordance with Heydekampf, No. 2,081,598, and O. S. Peters, No. stressand strain of a. specimen. 2,081,599. For purposes of specific referenceand A further object is to provide an improved illustration, it will beconsidered herein that the combination as above described that will berelamechanism of either one of said patents is used 25 tively economicalin manufacture, maintenance in this application, although the same isnot disand operation, that will allow minimum amount closed hereinbecause it does not constitute a part of record paper to be usedconsistent with desired of the present invention. A recorder drumgenresults, that will be positive and yet flexible in erally indicatedat 2 is formed preferably as a operation and adjustment Withoutsacrifice of the sheet metal cylin er having One end p 3 precisionqualities of such apparatus and that manently s ed to a fl ed end Cover4- his will be compact and yet readily accessible for cover is securedto shaft 5 in any suitable maninspection and repair. ner although it isspecifically shown as being I have found that the foregoing objects canheld by a nut 6 which clamps the cover against be obtained mostefiiciently by utilizing in one a shoulder on said shaft. As shown inFig. 2, 35 specific aspect of the invention a frictionally the drum isprovided with a longitudinal periphdriven recorder drum so formed andmounted as oral slot gene a y indicated at One e of the not only toreceive and house a roll of record slot bein of t Same thickness as t eepaper but also to permit the Sam t b metal and the adjacent edge beingturned back wound over the exterior of the drum and clamped underneathas generally indicated at 8 40 thereto in such a manner that successivepor- Vide smooth Inclined Surface over Whlch the tions of the recordpaper may be easily and effecf pafiper 1S unwound from papal: r011tively torn off, that the paper may be maintained Thls ml] 15 Supportedupon shaft 5 and 15 urgid taut over the drum surface and that apredeterone end of dr g pressgre i g mined ordinate line may be broughtinto precise ig fi bsuppmteqt ,2 s a 3 abgmst operative relation to therecording stylus. e m y any Sm a e spun" spam ca y S own as a s iralcoil I! which abuts a ainst a. remov- Other objects and advantges willbe more app g able end cover l2. The right end of the paper parent tothose skilled 1n the art from the fol- 1.011 (Fig 5) bears against theelement Hy Spaced 5 lowing description of the accompanying drawings fromthe ends of the drum. End cover I2 is proin WhiCh vided with a flangedportion to telescopically rel i a perspective f a recording app r ceivethe end of drum 3 and is held in position tus embodying my invention; bya nut l3 threaded on shaft 5. It is thus seen Fig. 2 is an enlargedperspective of the rethat shaft 5, the roll of paper, the pressure platecording drum and certain of the associated drivand the-drum structureform a self-contained 55 ibracket during rotation of screw 32.

drum unit. It is also preferable to include some driving mechanism aspart of the self-contained unit as will be presently described.

To support the drum unit, the ends of shaft 5 are provided with conicalrecesses I4 and I5 to receive tapered ends of screws I6 and II. Theshaft I6 is adjustably threaded in a suitable bracket I8 supported onthe top of base I. A hand grip I9 permits adjustment of screw I6 torelease the drum. The shaft I1 is adjustably threaded in a bracket 20supported on base I. Supported on shaft 5 in such manner as to permitrotation thereon are a driven gear 2I and friction driving meanscomprising preferably a pair of diametrical spring arms 22 secured togear 2| by screws 2 la or other suitable means. These arms are providedwith friction elements such as cork faces 23 engaging end cover 4. Ahand grip 24 is formed integrally with screw I'I. From the foregoing itis seen that gear 2| and the drum are rotated as a unit on the taperedends of the screws with resultant minimum frictional resistance, thusinsuring maximum accuracy in the transmission to the drum of factors tobe recorded. In addition the self-contained unit may be bodily removedwithout disturbing the relative relation of the driving parts.

As shown in Figs. 1, 3 and 4 there is mounted over the top of the drum astylus or pencil 25 and operating mechanism therefor. This mechanismincludes a guide shaft 26 secured in brackets 21 which extend upwardlyand rearwardly from the brackets I8 and 20. slidably supported on shaft26 is a U-bracket 28 within which a stylus arm 29 is disposed and isalso slidably and pivotally mounted on the shaft. The stylus 25 issuitably mounted in the outer end of arm 29. To pre vent rotation ofbracket 28 there is provided an arm 38 extending rearwardly and havingslidable connection. with an angle member 3| which extendslongitudinally between the brackets 21. To move longitudinally thebracket 28 and associated elements, there is provided a screw shaft 32and a pin'or follower member 33 disposed in the threads. This pin issupported in a shiftable depending arm 34, preferably somewhat flexible,secured by a screw to bracket 28. The connection between arm 34 andbracket 28' is sufiiciently strong to insure axial movement of the Toadjust the stylus longitudinally along its shaft 25 independently ofscrew 32, there is provided a cam surface 35 on arm 29, this camengaging a cam follower pin 3? projecting downwardly through bracket 23to engage spring arm 34. Hence upon rotating arm 29 upwardly about shaft26, cam 36 will press pin 37 downwardly and hence cause arm 34 to flexnear screw 35 to act as a fulcrum. This results in pin 33 being movedlaterally as shown in dotted lines at 39, thereby becoming free of thescrew and permitting independent longitudinal adjustment of the stylusalong shaft 26. When the stylus has been properly positioned, it is onlynecessary to lower the arm 29 whereupon arm 34 will spring the pin 33back into engagement with the threads of shaft 22. Hence it is seen thatmultiple functions are performed by the single movement of the arm 29,one function being the removal of the stylus from the recording drum andthe other the disengagement of the driving connection for the stylus.

To rotate screw shaft 32, a suitable power driven vertical shaft 4!extends upwardly from base I. This shaft drives a worm and pinion gear43, a

horizontal shaft 42, gears 44 and 45 and a friction drive secured toscrew shaft 32 thereby to rotate the same in response and in proportionto strain of the specimen.

The drum is operated preferably in response to stress of the specimenand to accomplish this I employ the operating mechanism such as shown insaid Peters application except instead of transmitting power to the drumthrough a string drive I employ a gear drive including a gear 48 fordriving the gear 2 I. This latter gear in turnv rotates friction arms 22so as to rotate the drum in proportion to stress. It will of course beunderstood that the drum could be rotated in accordance with strain andthe stylus moved in accordance with stress if so desired.

Operation-It will be assumed that the materials testing machine andspecimen are fully set up therein and connected to the recordingapparatus so that strain of the specimen controls power operation ofshaft 4! and the stress controls operation of gears 48 and 2 I. Thestylus arm 29 will then be raised by the operator so as to free pencil25 from the record drum and release pin 33 from screw shaft 32,whereupon the stylus will be moved to the left to a starting position asshown in Fig. l. A fresh record sheet, if such is necessary, can now bepulled upon the drum by first lifting a holding down bar 52, one end ofwhich is freely disposed in a socket 53 supported on the flange of endcover 4 and the other end of which is preferably frictionally heldbeneath a yieldable clip 54 secured on the flange of the other end coverI2. Clip 54 has one end open so that bar 52 can be moved in. acircumferential direction beneath the clip 54. The holding down barpreferably overlies slot I so as to hold down the paper on each side ofthe slot, thereby insuring that each successive portion of paper isuniformly held on the drum surface. With the end of the bar 52 removedfrom clip 54, the end 55 of the paper can be taken hold of by thefingers and pulled until a sufficient amount of fresh paper has beenunwound from roll 9, the paper passing over edge 8 and around the drumand under the partially removed holding bar, after which bar 52 isplaced in its holding position as shown in Fig. 2 and the loose end ofthe paper then torn off by using bar 52 as a tearing edge. Thus in thesingle operation a new portion of sheet is tautly drawn over the drumand the old portion of sheet moved to a tearing off position. It willoften happen after providing a fresh portion of the record sheet thatthe stylus does not fall upon a predetermined ordinate line at which itis desired to start the record. To obtain this desired cooperativerelation, it is only necessary for the operator to rotate the drum 3with his fingers, during which time the frictional arms 22 allowslippage so that the drum rotates independently of the gear transmission43 and 2 I. Or if desired, suitable markings may be placed on the flangeor flanges of the end cover to indicate that when an ordinate line isopposite such markings, then the stylus will initially rest on thatordinate line. In such case, the paper would be pulled around the drumuntil the ordinate line and end marking are in register. To adjust thestylus to any predetermined abscissae line, either one of knobs 49secured to the opposite ends of screw 32 is turned with the fingersthereby rotating screw 32 to move the stylus carriage with the stylus toany desired position. Screw 32 is frictionally held by spring finger 55to gear 45 which slips when turned but without disturbing the gears.

After the roll 9 of record paper has been com pletely used, the operatormay substitute a new roll by grasping hand grip l9 and rotating screw itto release its tapered end from recess M, Fig. 5, whereupon the drumunit is bodily moved laterally from its frame. A recessed ledge 55 (Fig.6) having a laterally relieved side 56 permits shaft to be momentarilysupported while adjusting screw [5. The nut l3 and end cover l2 are thenremoved from shaft 5 together with the spring l i and pressure plate Hi.The holding bar 52 is likewise removed. A new roll is then inserted, aportion of unrolled paper being inserted into the end of the drum slot 1at the time when the roll is inserted within the drum. After the rollhas been inserted, pressure plate Hi, spring II and end cover 12 areplaced on shaft 5 together with nut I 3 to urge the roll to the rightend of the drum. The drum is then inserted between the pedestals l8 and20 and screw I6 rotated to seat in conical recess l4. The paper is thenpulled around drum 3 after which holding bar 52 is pushed under clip 54to hold the paper in position. As previously stated, if the stylus 25does not coincide with desired ordinate and abscissae lines on therecord paper, then drum 3 is partially rotated by hand against thefrictional contact of friction arms 22, and knob 49 is rotated againstthe frictional contact of spring 50. If it is desired to shift thestylus longitudinally without raising it from the drum, then the leftend of an arm 51, pivoted at 58 so as to be out of the vertical plane ofarm 29, is moved upwardly by the operators fingers to cause the shortcam-like right end 59 to engage a lateral extension (not shown) ofsupport 34 and force it down with the same result as if done by pin 31.

From the foregoing disclosure it is seen that I have provided animproved recording apparatus whereby fresh record paper may be not onlyconveniently and expeditiously placed in use but at the same timeeffectively brought into proper cooperative relation with the stylus,this improved combination being relatively economical in manufacture,maintenance and operation and insuring that a minimum amount of recordpaper will be used consistent with desired results without in any wayimpairing the positive and yet flexible operation of the apparatus orits precision qualities.

It will of course be understood that various changes in details ofconstruction and arrangement of parts may be made by those skilled inthe art without departing from the spirit of the invention as set forthin the appended claims.

I claim:

1. Recorder apparatus comprising, in combination, a rotatable hollowrecorder drum having a longitudinal peripheral slot, a roll of recordpaper adapted to be disposed within said drum, a portion of the paperextending outwardly through said slot and around said drum and acrosssaid slot into overlapping relation with the portion of the paperextending immediately outwardly through said slot, and means movablewith said drum for positively pressing and thereby directly tightlyclamping the overlapped portions of said paper to the periphery of saiddrum longitudinally thereof, the clamped portions of paper beingdisposed directly between the drum and clamping means and said clampingmeans being movableaway from the drum to release said pressing actionand allow the paper to be freely unwound.

2. Recorder apparatus comprising, in combination, a hollow recorder drumhaving a longitudinal peripheral slot, a roll of paper adapted to bedisposed within the drumand having a portion extending through said slotand around the surface of the drum and terminating adjacent said slot,and a holding down bar supported entirely by said drum and bridging oversaid slot to positively press and thereby directly tightly clamp thepaper on to the drum at opposite longitudinal sides of said slot, theclamped portion of paper being disposed directly between the drum andclamping means.

ORV'ILLE S. PETERS,

